(1) Field of the Invention
The present invention relates generally to a bi-directional rotation transfer device that allows free and independent precession of the dependent rotating element and, more particularly, to a locomotion differential rotation assembly for full-time, full-power, all-wheel drive.
(2) Description of the Prior Art
A locomotion differential is a gear assembly connectable between the traction wheels of a vehicle for permitting different wheels to turn at different speeds relative to one another at the same time. This ability to turn independently is especially important when going around a corner or on uneven terrain since one wheel may have to turn at a different rate than another. For example, when going a corner the inside wheels turn more slowly than the outside wheels. If both wheels were required to turn at the same rate, the vehicle would not move smoothly through turns due to the fact that the wheels would tend to bounce or scrub the traction surface in order to maintain their rate of rotation. Thus, the wheels would periodically loose traction with the surface. Such a vehicle would be dangerous at high speeds, as centrifugal forces acting on the vehicle in the turn would cause it to move sideways in the turn whenever the wheels lost traction with the surface. Additionally, four-wheel drive or all-wheel drive vehicles require a differential between the front and rear axle for similar reasons. A device that would allow freewheeling, or the unhindered super-rotation in the direction of locomotion, would be desirable for such situations, in that the rotation of such a wheel would not be restrained and cause the aforementioned problems.
Various types of differentials also exist to improve traction under slippery conditions. These differentials work by basically slowing or stopping the rotation of the wheel that is slipping. For example, a locking differential reacts when one wheel or axle starts slipping by firmly locking up the gears to prevent that slippage. A limited slip differential limits the speed and torque differences between two wheels on an axle, or between front and rear axles in the case of 4-wheel drive/all-wheel drive, but does not completely lock-up a wheel or semi-axle. By allowing limited slip, the differential ensures that some power is always applied to each of the wheels, even when one is on a slippery surface.
Thus, a differential has to both allow the wheels or axles to rotate independently on one another to prevent loss of traction in a turn, but must also prevent excess slippage to prevent loss of traction under poor traction conditions. Such a device, therefore, has to perform two opposing functions: 1) allow increased differential rotation between wheels or axles, but 2) prevent excessive differential rotation between the same.
Typically, prior art differentials commonly employ complicated mechanical devices to transfer power. Additionally, these differentials usually transfer power to only 1 pair of semi-axles at a time. Thus, a multi-axle vehicle would require several of these differentials: first, it would require a differential to transfer the power between the axles, then, a differential to transfer power between semi-axles. Additionally, these prior art differentials are attached or in close proximity to the transmission, making them difficult to replace and maintain. Frequently, the transmission and/or differential cannot be replaced singularly. Thus, prior art differentials are complex, expensive, and difficult to maintain and replace.
Thus, there remains a need for a differential that can function effectively and not be expensive to manufacture and/or maintain.
The present invention is directed to a rotation transfer device that allows bi-directional transfer of rotation and bi-directional freewheeling for at least one rotating element coupled therewith by the rotation transfer device.
Also, the present invention is directed to a rotation transfer device including a first rotating element, a second rotating element, and a rotation coupling mechanism that provide bi-directional transfer of rotation from the first rotating element to the second rotating element through the rotation coupling mechanism and bi-directional freewheeling of the second rotating element with respect to the first rotating element through the rotation coupling mechanism.
The present invention is further directed to a rotation transfer device for supplying differential function to a vehicle having multiple wheels and at least one axle to provide bi-directional transfer of rotation and bi-directional freewheeling to vehicular wheels.
The present invention is further directed to a rotation transfer device for supplying differential function to a vehicle having multiple wheels and at least one axle to provide bi-directional transfer of rotation and bi-directional freewheeling within non-vehicular machines.
Accordingly, one aspect of the present invention is to provide a rotation transfer device that allows bi-directional transfer of rotation and bi-directional freewheeling.
Another aspect of the present invention is to provide a rotation transfer device that allows bi-directional transfer of rotation and bi-directional freewheeling for at least one rotating element coupled therewith by the rotation transfer device, including a first rotating element, a second rotating element, and a rotation coupling mechanism that provide bi-directional transfer of rotation from the first rotating element to the second rotating element through the rotation coupling mechanism and bi-directional freewheeling of the second rotating element with respect to the first rotating element through the rotation-coupling mechanism.
Still another aspect of the present invention is to provide a differential system for a vehicle, wherein the differential system includes at least one rotation transfer device having a first rotating element, a second rotating element, and a rotation coupling mechanism, wherein bi-directional transfer of rotation from the first rotating element to the second rotating element is accomplished through the rotation coupling mechanism and bi-directional freewheeling of the second rotating element with respect to the first rotating element is accomplished through the rotation coupling mechanism.
Still another aspect of the present invention is to provide a differential system within a non-vehicular machine wherein the differential system includes at least one rotation transfer device having a first rotating element, a second rotating element, and a rotation coupling mechanism, wherein bi-directional transfer of rotation from the first rotating element to the second rotating element is accomplished through the rotation coupling mechanism and bi-directional freewheeling of the second rotating element with respect to the first rotating element is accomplished through the rotation coupling mechanism.